<!DOCTYPE html>
<html>

<head>
  <meta http-equiv="content-type" content="text/html; charset=utf-8">
  <meta name="viewport" content="width=device-width,initial-scale=1,maximum-scale=1,user-scalable=no">

  <title>侧边展开导航栏</title>
  <!-- 引入字体图标 -->
  <link rel="stylesheet" href="https://cdn.staticfile.org/font-awesome/4.7.0/css/font-awesome.css">
</head>
<body>
<div class="navbar">
  <input type="checkbox" id="checkbox">
  <label for="checkbox">
    <i class="fa fa-bars" aria-hidden="true"></i>
  </label>
  <ul>
    <li>
      <img src="../static/img/logo.png"></img>
      <span>管理员端</span>
    </li>
    <li>
      <a href="../AdminMangement/UserManage.jsp" target="center">
        <i class="fa fa-home" aria-hidden="true"></i>
        <span>用户管理</span>
      </a>
    </li>

    <li >
      <a href="../AdminMangement/TicketMange.jsp" target="center">
        <i class="fa fa-sitemap" aria-hidden="true"></i>
        <span>航班管理</span>
      </a>
    </li>
    <li>
      <a href="../AdminMangement/AdminUpdateThemself.jsp" target="center">
        <i class="fa fa-user-circle-o" aria-hidden="true"></i>
        <span>个人信息管理</span>
      </a>
    </li>
  </ul>
</div>
</body>
<style>
  *{
    /* 初始化 取消内外边距 */
    margin: 0;
    padding: 0;
  }
  body{
    /* 溢出隐藏 */
    overflow: hidden;
  }
  .navbar{
    /* 相对定位 */
    position: relative;
    /* 100%窗口宽度 */
    /*width: 100vw;*/
    display: flex;
  }
  .main{
    flex: 1;
    height: calc(100vh - 43px);
    position: relative;
    top: 43px;
    display: flex;
    justify-content: center;
    align-items: center;
  }
  .toWhite{
    background-color:white;
  }
  #checkbox{
    display: none;
  }
  .navbar label{
    position: absolute;
    top: 0;
    left: 70px;
    width: 100%;
    height: 43px;
    font-size: 30px;
    color: #5a738e;
    background-color: #ededed;
    padding-left: 20px;
    border: 1px solid #d9dee4;
    cursor: pointer;
    /* 加个动画过渡 */
    transition: all 0.5s;
  }
  .navbar ul{
    list-style: none;
    width: 70px;
    /* 100%窗口高度 */
    height: 100vh;
    background-color: #2a3f54;
    transition: all 0.5s;
    overflow: hidden;
  }
  .navbar ul li{
    height: 70px;
    margin-bottom: 10px;
  }
  .navbar ul li:first-child{
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 0 10px;
  }
  .navbar ul li:first-child img{
    width: 50px;
    height: 50px;
    border-radius: 50%;
  }
  .navbar ul li:first-child span{
    /* 先把文字隐藏起来 */
    display: none;
    color: #fff;
    /* 文字禁止换行 */
    white-space: nowrap;
    padding-left: 10px;
  }
  .navbar ul li a{
    display: flex;
    justify-content: center;
    align-items: center;
    /* 垂直排列 */
    flex-direction: column;
    width: 100%;
    height: 100%;
    color: #d1d1d1;
    text-decoration: none;
  }
  .navbar ul li a i{
    font-size: 25px;
    margin-bottom: 10px;
  }
  .navbar ul li a span{
    font-size: 12px;
    white-space: nowrap;
  }
  .navbar ul li a:hover{
    color: #fff;
    background-color: #35495d;
  }
  /* :checked选择器是判断复选框是否被选中 */
  /* +是相邻兄弟选择器，找到input的下一个兄弟label */
  .navbar input:checked + label{
    left: 200px;
  }
  /* ~也是兄弟选择器，但它可以找到隔了几代的兄弟 */
  .navbar input:checked ~ ul{
    width: 200px;
  }
  .navbar input:checked ~ ul li:first-child{
    /* 将居中改为开头对齐 */
    justify-content: flex-start;
  }
  .navbar input:checked ~ ul li:first-child span{
    /* 文字显示 */
    display: block;
  }
  .navbar input:checked ~ ul li a{
    flex-direction: row;
    justify-content: flex-start;
  }
  .navbar input:checked ~ ul li a i{
    font-size: 18px;
    margin: 0 15px 0 30px;
  }
  .navbar input:checked ~ ul li a span{
    font-size: 14px;
  }
</style>
<script>
  window.addEventListener('DOMContentLoaded', function() {
    let checkbox = document.getElementById('checkbox');
    checkbox.checked = true;
  });
  let index=1;
  function change(target) {
    index=target
  }
</script>
</html>
